The Moon

The moon, the only natural satellite
orbiting Earth, is the Earth's closest neighbor in space. This cold, rocky
body is about 384,403 kilometers (238, 857
miles) away. Traveling there is like going around the earth 10 times.Here is a current
view of the Moon from Earth.

Size

The
moon is 3476 kilometers (2,160 miles) in diameter. It is 1/4 the size of
the earth. It is about 400 times smaller than the sun, and 400 times closer.
Because of this, the sun and moon appear to be the same size.
Here
is a view of Earth
from the Moon

AgeMaterial

The
moon is very old!!!

Scientists believe that about 4.5 billion years ago a Mars-sized body
hit Earth and the resulting debris (from both Earth and the impacting
body) accumulated to form the Moon. Scientists know this because they
studied the lunar rocks that were collected by astronauts who went to
the moon. The moon and the earth are made of the same material. It has
a small iron core. Read
More...

The Moon has no atmosphere so the lunar sky is black. You need atmosphere
to make the sky blue. You must carry your own air for breathing. Photos
of the moon from Space Funny
stuff: Did you hear about the restaurant on the moon?
The
food is terrific, but there's no atmosphere.

The
same side of the moon always faces earth so, you can only see one side.
See the photo
astronauts took of the far side...

The moon orbits,
or revolves, around the Earth about
once every 27 days, 7 hours, 43 minutes.
This movement causes the moon to cycle through a series of phases:
New, New Crescent, First Quarter, Waxing
Gibbous, Full, Waning Gibbous, Last
Quarter, Old Crescent and back to New again.

The
moon has no light of its own. It shines because sunlight is reflected
from its surface.

What
is "moonrise?" The Earth rotates
once a day on its axis causing the phenomena of the rising and setting of
the sun and moon. They seem to appear in the sky at the horizon to the East,
then to cross the sky and disappear at the horizon to the West. Photo

Sometimes
the moon passes through some portion of the earth's shadow and the Earth
blocks part or all of the sun's rays from reaching the moon.

Are
you curious about the Names
of the Full Moons?
Investigate this in depth chart
from different cultures.

The
Landscape of the Moon

mare terre craters rays rilles .

16% of the lunar surface is covered by dark areas called maria
which are areas of hardened lava. Maria means "seas". We can
easily see these dark areas from earth. Photo1,
Photo
2, Photo
3

The brighter cratered
highlands are called terrae. The craters
here were formed by meteorite impacts.

The streaks
of light-colored material ejected from craters on the moon are called
rays.Click on the photo above and try to identify the features.

The trench running
across the middle of this Apollo
10 image is a rille called Rima Ariadaeus. Rilles are common on the
moon and are thought to be the remnants of lava flows or collapsed lava
tubes. Rima Ariadaeus is a long straight rille, around 3-5 km (2-3 miles)
wide and 225 km (140 miles) long, and is seen here from about 14 km (9
miles) above the lunar surface.

Man
on the Moon

It
took about 360 years from when the Italian astronomer Galileo Galilei made
his first observation of the Moon with a telescope in 1610 until the Apollo
11 mission made the first landing on the Moon and returned samples in 1969.
Don't miss the great Apollo 11 story from NASA
complete with audio, video, and photos.